受冻稻谷薄层干燥特性试验研究

发布时间：2018-06-20 23:10

  本文选题：热风 + 薄层干燥　； 参考：《黑龙江八一农垦大学》2017年硕士论文

【摘要】：省委农村工作会议提出要高度重视我国农产品精深加工项目建设,在保证农业稳定发展与农民持续增收的基础上,走产出高效、产品安全、资源节约、环境友好的农。业现代化道路,推动黑龙江农业大省向农业强省战略转变。由于黑龙江地区稻谷产量大,生产效能与稻谷产量存在矛盾。稻谷在收获后,在堆放过程中易受冻,将此状态下的稻谷称之为受冻稻谷。稻谷受冻后,构成膜的脂类发生转变,由液相转为固相,导致与膜相结合的酶失去活性,细胞膜的透性会改变,细胞内的新陈代谢活动会受影响。如果干燥过程中不加区分,采用和常态下稻米相同的干燥工艺参数,爆腰现象剧烈,烘后品质会下降,影响优质米经济效益。针对冻态稻谷干燥后品质降低等干燥生产瓶颈问题,以受冻稻谷垦粳5号为试验材料,利用双向通风薄层干燥实验装置研究受冻稻谷薄层干燥特性,提高东北低温地区稻谷稻米品质和商品粮经济效益。首先,阐述了横向-双向通风薄层干燥实验装置的设计及优势创新点。采用水平送风垂直称重被实验物料,提高了试验谷物的称重精度。干燥过程中不用停止风机就可以利用动态在线称重系统称取某一时刻干燥物料的重量,计算出含水率。其次,利用热风干燥技术,采用单因素试验设计,以干燥速率为评价指标,探究热风温度、热风表现速度、初始含水量、物料厚度对受冻稻谷干燥特性的影响。实验证明:风速和热风温度对受冻稻谷干燥特性影响大,风速越大,热风温度越高,干燥用时越短;初始含水率越低,干燥速率越慢;物料厚度越厚,干燥效率越慢。在相同干燥条件下,受冻稻谷干燥效率低于常规稻谷干燥效率,整精米率高于常规稻谷。通过多因素通用旋转组合试验,以爆腰增值率、直链淀粉含量、米饭食味值为综合评价指标,利用MATLAB、ORIGIN等软件对实验结果进行处理分析,得出受冻稻谷薄层干燥工艺参数组合:热风温度为30℃,热风表现速度为0.1m/s,初始含水率为18.2%,物料厚度为2.0cm,烘后爆腰增值率为1.8%,直链淀粉含量为16.3%,米饭食味值得分为87.9分。受冻稻谷经过低温干燥才能提高整精米率和食味值。
[Abstract]:The Rural work Conference of the Provincial Party Committee proposed that we should attach great importance to the construction of intensive processing projects for agricultural products in our country. On the basis of ensuring the stable development of agriculture and the continuous increase of farmers' income, we should take the agriculture with high output efficiency, product safety, resource saving and environmental friendliness. Industry modernization road, promote Heilongjiang agriculture big province to agriculture strong province strategic transformation. Due to the large yield of rice in Heilongjiang region, there is a contradiction between the production efficiency and the yield of rice. After harvest, the rice is easy to freeze in the process of stacking, so the rice in this state is called frozen rice. After rice was frozen, the lipids of the membrane changed from liquid phase to solid phase, which resulted in the loss of enzyme activity, the membrane permeability and the metabolic activity in the cell. If no distinction is made in the drying process and the same drying process parameters are adopted as under normal conditions, the phenomenon of blow-blasting is violent, and the quality after drying will decrease, which will affect the economic benefit of high-quality rice. In order to solve the bottleneck problem of frozen rice drying, the drying characteristics of frozen rice thin layer were studied by using two-way ventilation thin-layer drying experiment device, in which the frozen rice Kengjing No. 5 was used as the experimental material. Improve rice quality and economic benefit of commercial grain in Northeast China. Firstly, the design and advantages of transverse-two-way ventilation thin-layer drying apparatus are described. The weighing precision of test grain is improved by using horizontal air supply vertical weighing material. In the drying process, the dynamic on-line weighing system can be used to weigh the dry material at a certain time without stopping the fan, and the moisture content can be calculated. Secondly, using hot air drying technology, single factor experimental design and drying rate as evaluation index, the effects of hot air temperature, performance speed of hot air, initial moisture content and material thickness on the drying characteristics of frozen rice were investigated. The experimental results show that the wind speed and hot air temperature have great influence on the drying characteristics of frozen rice. The higher the wind speed, the higher the hot air temperature, the shorter the drying time, the lower the initial moisture content, the slower the drying rate, the thicker the material thickness, the slower the drying efficiency. Under the same drying conditions, the drying efficiency of frozen rice was lower than that of conventional rice, and the whole head rice rate was higher than that of conventional rice. Through the multi-factor general rotation combination test, the experiment results were processed and analyzed by the software MATLABORIGIN, taking the appreciation rate of exploding waist, amylose content and rice taste value as the comprehensive evaluation indexes. The results showed that the drying process parameters of frozen rice were 30 鈩，

本文编号：2046043